HIPEC (Hyperthermic Intraperitoneal Chemotherapy)

Total procedure time is 6-12 hours. Cytoreductive surgery (removing all visible tumor) takes 4-10 hours depending on disease extent and number of organs involved, followed by HIPEC perfusion lasting 60-90 minutes. The open (Coliseum) technique keeps the abdomen open during perfusion for manual agitation and temperature uniformity, while the closed technique closes the abdomen for lower heat loss.

The heated chemotherapy solution is maintained at 41-43°C, with a goal tissue temperature of 42-42.5°C. This elevated temperature (hyperthermia) enhances chemotherapy penetration into tumor tissue, increases drug cytotoxicity, and directly damages cancer cells. The heat also improves chemotherapy absorption in the first 1-2mm of tissue where microscopic disease resides after cytoreduction.

The most common agents are Mitomycin C (35 mg/m² over 90 minutes, preferred for colorectal/appendiceal per PRODIGE 7 findings), Cisplatin (50-100 mg/m² over 60-90 minutes for ovarian/gastric/mesothelioma), and Oxaliplatin (350-460 mg/m² over 30-60 minutes, limited evidence per PRODIGE 7). Drug selection depends on cancer type and institutional protocols. Cisplatin is often combined with Paclitaxel for ovarian cancer.

The Peritoneal Cancer Index (0-39) divides the abdomen into 13 regions, scoring each 0-3 based on tumor size. Lower scores indicate better HIPEC candidacy. Per 2025 MSK Consensus Guidelines for colorectal cancer: PCI ≤12 indicated, 12-17 uncertain, >17 contraindicated. Appendiceal cancer (low-grade PMP) can proceed with PCI up to 39 if complete cytoreduction is achievable. CT imaging detects only 47.8% of disease versus 100% with diagnostic laparoscopy.

Survival varies significantly by cancer type and completeness of cytoreduction (CC-0). Appendiceal (low-grade PMP): median >100 months, 70-85% 5-year, 50-70% 10-year survival—best outcomes (Chua TC et al., Ann Surg Oncol 2012). Colorectal peritoneal metastases: median 22-60 months, 20-50% 5-year survival with CC-0 and PCI ≤20 (Elias et al., Ann Surg 2010). Ovarian (interval surgery): median 52-57 months, 40-60% 5-year survival (CHIPOR trial, van Driel WJ, NEJM 2018). Gastric: median 12-18 months—most aggressive (Glehen et al., J Clin Oncol 2010). Approximately 16% cure rate with macroscopically complete resection. Individual outcomes vary based on disease extent, patient health, and surgical completeness.

Minimum Thailand stay is 6-8 weeks total: 1-2 weeks pre-operative evaluation, 10-14 days hospitalization, and 3-4 weeks recovery before long-haul flight. Earlier travel may be considered for shorter flights with appropriate precautions. All flights require graduated compression stockings, ambulation every 1-2 hours, aggressive hydration, and extended VTE prophylaxis may be recommended. Business/first class is advisable for space to recline.

Many patients benefit from adjuvant systemic chemotherapy starting 6-12 weeks after surgery once adequately recovered. Colorectal: FOLFOX, FOLFIRI, or 5-FU based (3-6 months). Appendiceal (low-grade): usually surveillance only. Ovarian: platinum-based (6 cycles). Gastric: FLOT or similar. Mesothelioma: pemetrexed + cisplatin (4-6 cycles). Decisions are made by the oncology team based on cancer type, pathology, and individual factors.

Cytoreductive surgery removes all visible tumor from the abdominal cavity before HIPEC. It may include removal of affected organs or portions: omentectomy, peritonectomy, bowel resection, splenectomy, cholecystectomy, or gynecologic organ removal. The goal is complete cytoreduction (CC-0, no visible disease) or CC-1 (under 2.5mm residual). Complete cytoreduction is the most important prognostic factor—5-year survival approaches zero if PCI >20 for colorectal cancer.

Absolute contraindications include: distant metastases beyond peritoneum (liver >3 metastases, lung, bone, brain); unresectable disease (root of mesentery, hepatic pedicle, retroperitoneum invasion); PCI exceeding cancer-specific thresholds; ECOG performance status ≥3; severe cardiac/pulmonary disease; active infections; pregnancy. Relative contraindications include signet ring cells, prior extensive radiation, age >70-75 with poor functional status, and partial response to neoadjuvant chemotherapy.

Thailand comprehensive costs: $20,000-$40,000 including surgery, HIPEC, hospitalization, and basic follow-up. US costs: $80,000-$200,000. Component breakdown—Surgeon fee: Thailand $5,000-$8,000 vs US $15,000-$30,000; Hospital/facility: Thailand $10,000-$20,000 vs US $40,000-$100,000; ICU per day: Thailand $1,000-$2,000 vs US $5,000-$10,000. Government/university hospitals may offer lower costs. Savings: 50-80%. Verify current pricing directly with hospitals.

Per academic research (PMC6397120), only 7 centers in Thailand perform CRS-HIPEC, with 90% at government university hospitals (Siriraj, Chulalongkorn). Vejthani Hospital (Life Cancer Center) is a confirmed private hospital HIPEC provider with Dr. Worapong Anuponganan, JCI and GHA accredited, with a dedicated HIPEC program page. Bumrungrad, Bangkok Hospital/Wattanosoth, and MedPark have comprehensive oncology services but HIPEC availability should be verified directly. Only 5 surgeons regularly perform these procedures in Thailand.

Essential documents include: complete operative report with CC score, PCI, and procedures performed; pathology report with tumor staging; HIPEC chemotherapy documentation (agent, dose, duration, temperature); discharge summary; all imaging on CD or digital; follow-up surveillance recommendations; medications at discharge; 24/7 contact information for Thai hospital. Telemedicine follow-up consultations are available through hospital international services.

Surveillance varies by cancer type but typically includes: CT every 3-6 months for years 1-2, then every 6 months through year 5, then annually. Tumor markers (CEA, CA-125, CA 19-9 as applicable) at each visit. Clinical exam at each visit. Colonoscopy per guidelines if colorectal origin. Signs requiring attention: new abdominal pain/distension, unexplained weight loss, bowel obstruction symptoms, rising tumor markers, new imaging findings, chronic fatigue.